has anyone ever tried the boric acid and alcohol treatment before soldering..if so what is your opinion and what is the proper way to mix the two ...thanks

You can use a jam or mustard jar (depending on the size of the metal piece) with an sealable but easy to open lid.
The borax/boric acid powder settles at the bottom of the mixture after just a little time.
Start with 3/4 dry powder to liquid ratio.
When settled, you want about 1/2 of the mix to be the white borax.
Shake each time before use to put the borax into suspension, dip the piece and place it on your soldering pad/screen ... then immediatelly light it to burn off the alcohol.
The result should be a nice even visible coating of powder.
Although borax/boric acid is found in most fluxes this is not enough to endure brazing in most cases. Apply our favorite flux at this point IN ADDITION to this age old fire scale prevention method. If you are using liquid flux keep the piece warm while dabbing the seams with farily large brush (like camel hair). This method causes the flux to dry quickly without running. A bigger mop-like brush maintains enough liquid so it's hair ends does not stick to the warm metal. The trick is to keep the metal just right. Too cold, the flux will run ... too hot and your brush will stick to the too hot surface

Please correct me if I'm wrong John, but in Glen F. Waszek's book "Making Silver Chains",
he says boric acid and borax are not the same thing.

True, that's why I wrote "borax/boric acid" as some people use one and others recommend and use the other.
Back in the 60's I learned about this method from Oppi Untracht's first "Metal Techniques..." book and liked powdered borax a little better because it was very fine, went into solution very easily and deposited a nice even coating instead of being lumpy.

I'd be truly interested in which one really works best and suspect boric acid would win a poll.

Note: Later on in my silver smithing career in the late 70's I met an extremely interesting fellow in Phoenix who'd invented a solution he called Cuprinol. Where the age old boric acid or borax and alcohol did leave some fire scale plus some slag needing to be pickled, a good even coating of Cuprinol left everything I made virturally firescale free ... including large boxes and service pieces that had been totally brought up to brazing temperature up to a dozen times. There was no need for depletion gilding over fire scale in my camp!
The down side is that Cuprinol is much more expensive to use than the old fashioned boric/alcohol method.

Great info I HATE FIRE SCALE

thanks so much

I normally mix mine 1/3 boric to 2/3 denatured alcohol. (depends on evaparation main thing is about 2% milk consistancy when stired)
stir it well each time and apply with the cammel hair brush
a little differnt than how John does but it works for me.
then I always mix my fluxes about the same with distilled water.
about the same 1/3 - 2/3 distilled water, applying it with just a small soft finedetail brush on the solder and connecting joints .

D

Thanks for clarifying John, i'm mainly observing at the moment and sometimes the info can be very confusing and contradictory. I have soldered and annealed etc but it was a couple of years back in a class situation. I'm trying to get a studio set up at home so i can continue with this wonderful and expressive art form but it's very hard to know what to spend the money on. Also in Australia (and especially Tasmania) it's hard to find supplies, i can get borax at the supermarket but boric acid is nearly impossible to find.

Did you try the drugstore?
Thats usually where I pick it up. Hey after all they use it in eye drops.

[:D]
D

Sure did D, about three years ago in Aus it was classed as a poision so they aren't allowed to keep it. We do have a couple of (only 2!) jewelry supply stores on the mainland but would you believe they don't have online stores, talk about the dark ages!

FWIW I use either the denatured alcohol/boric acid solution or cuprinol. Both work extremely well. And I kinda like the glow of the pretty green flame when it burns off ... ok ... I've been at the bench WAY too long today and it's showing!

Does anyone know why it has to be alcohol mixed with the borax/boric acid?
If it's only used to suspend the acid why can't you just use water?
Forgive my ignorance, I was always terrible at chemistry [D)]

Thats funny.... Its a major ingrediant in most cockroach killers, they just add a little sugar w/ it.
But there is so much more stuff more dangerous than that.
The denatured alcohol burns off cleanest leaving a even coating when it is heated. Water takes longer to evaporated off thats why when you mix your flux with water you have to warm the piece a little at a time till the flux gets crunchy looking then you can start with a more serious heat.
thats the practical side skiping over all of how the molecular combinations break down.

D

Wow, even I understood that. [:O]

Your right I just looked on Wikipedia and it says it's not much more toxic than table salt.

Thanks for your info D, I guess i'll have to do a little more digging.